docs: def compute_center(
      feed: "Feed", num_busiest_stops: Optional[int] = None
  ) -> Tuple:
      """
      Return the centroid (WGS84 longitude-latitude pair) of the convex
      hull of the stops of the given Feed.
      If ``num_busiest_stops`` (integer) is given,
      then compute the ``num_busiest_stops`` busiest stops in the feed
      on the first Monday of the feed and return the mean of the
      longitudes and the mean of the latitudes of these stops,
      respectively.
      """
      s = feed.stops.copy()
      if num_busiest_stops is None:
          hull = compute_convex_hull(feed)
          lon, lat = list(hull.centroid.coords)[0]
      else:
          date = feed.get_first_week()[0]
          ss = feed.compute_stop_stats([date]).sort_values(
              "num_trips", ascending=False
          )
          if ss.stop_id.isnull().all():
              # No stats, which could happen with a crappy feed.
              # Fall back to all stops.
              hull = compute_convex_hull(feed)
              lon, lat = list(hull.centroid.coords)[0]
          else:
              f = ss.head(num_busiest_stops)
              f = s.merge(f)
              lon = f["stop_lon"].mean()
              lat = f["stop_lat"].mean()
  
      return lon, lat